1. Field of the Invention
The present invention relates to an optical beam scanning device used for a laser printer, a digital copying machine or the like, and relates to an attachment mechanism of a rotary deflector that deflects a light flux from a light source and scans it in a main scanning direction.
2. Description of the Related Art
Hitherto, there is known an optical beam scanning device using a rotary deflector, such as a polygon mirror, that deflects a light flux from a light flux and scans it in a main scanning direction (JP-A-2002-328323, U.S. Pat. No. 6,888,655, JP-A-2005-24958, JP-A-2005-49506, JP-A-2005-49509, JP-A-2005-62399).
In such an optical beam scanning device, an error in attachment of the rotary deflector to the device has a large influent on the optical characteristics of the optical beam scanning device. Particularly, as compared with an attachment error to cause the rotation of a post-deflection optical system around an optical axis, an attachment error to cause the rotation around an axis parallel to the main scanning direction has a large influence on a wave aberration, and causes an increase in beam diameter and a degradation in beam profile.